Shedding-mechanism of circular looms



Ud. w35. W, HOWARTH Emm SHEDDING MECHANISM OF CIRCULAR LOOMS Filed Aug. 4, 1935 WILMAM Hmmm Patented Oct. 8, 1935 UNITED STATES @ATENT GFFICE William Howarth, Spondon, near Derby, England, assigner to Celan-ese Corporation of America, a corporation of Delaware Application August 4, 1933, Serial No. 683,619 In Great Britain August 1S, 1932 .more especially concerned with the contro-l of the Warps in circular looms, and has for its object to devise shedding mechanism which Will be suitable for ne or very line Warp spacing and to enable fabrics to be Woven in a variety of patterns, either of small repeat, as for example in tv/ills, serges, and satins, or in designs of greater complexity.

In circular looms it is generally most convenient to arrange that the Warps in proceeding from the Warp beams, beam sections or other supply to the point of Weaving, as Well as the fabric proceeding to the take-up means, shall be in a generally cylindrical form, for by this arrangement the total diametral dimensions of the loom can be kept down to a reasonable size in relation to the diameter of the fabric being Woven. Consequently, the movement of the Warps to form a shed for the passage of the shuttle is required to be in a substantially radial direction, with the result that the shedding means employed must be caused to move substantially radially. It is also most desirable that movement of the shedding means should be substantially radial because of the importance of avoiding as far as possible rubbing of the vvarps or undue tensioning thereof, which would result from Warps .extending substantially coaXially of the loom being moved in other than a substantially radial direction. lThe provision of radially moving shedding means constitutes one of the difliculties which are met with in circular loom construction.

A further diiiiculty is encountered in circular looms because of the large warp density required in the majority of Woven fabrics, this density amounting to as much as 150 or even in some cases to 200 or more Warp ends per inch. Most usually it is desirable that each Warp thread should be under separate independent control, a circumstance which, in conjunction With close warp spacing, tends to make the shedding mechanism complicated vand difficult of operation. This is especially so when the shedding movement has to be performed on Warp threads which are substantially co-axial with the loom axis, necessitating substantially radial movement of the shedding means as mentioned above.

Though some of the difficulty attendant on the close spacing of the vvarps can be overcome by arranging the healds or like devices in a plurality of banks so that sufiicient space is provided for the healds and for the free passage between them of the Warps controlled by the other banks, there is at the same time the inconvenience that the separate control of the healds in the several banks is not easy to eiiect, especially as the banks should be fairly close together to keep down to a minimum the length of movement of the healds for a given Width of shed. Where the circular loom is 5 of the type in which the shuttles are kept stationary to avoid the necessity for the shuttlenolding means having to withstand considerable centrifugal force, it also becomes necessary to arrange that most of the elements of the .shedding mechanism shall be able to rotate with the Warps, and this in turn gives greater force to the necessity for compactness in the mechanism already imposed by the close Warp spacing, as Well as adding to the difliculty of driving the mechanism.

According to the invention, the shedding mechanism comprises a plurality of banks of fine shedding needles, each bank comprising closely spaced slots vadapted to permit sliding movement of the needles and to support the needles over a substantial portion of their length, and means to engage selected needles and to draw them under tension to perform a shedding movement in one direction.

The needles thus receive their operative movement by tension only, and so can be made Very iine and capable of close spacing. At the same time, the support accorded to the needles by the slots enables the needles to stand up to the action of the engaging means and provides for an easy motion of the needles. Preferably, the engagement of the needles by the operating means takes place Within the supported length of the needles, as by the provision of butts on the needles for engagement by cams in connection with each bank operating Within the length of the needle slots. A similar butt may serve to limit the movement of the needles in the reverse direction on their release from the cams, stops being provided in the slots to engage these further butts.

The reverse movement of the needles may be effected by the tension imparted to the warp threads in the shedding movement of the needles, or springs may be provided for this purpose. In either case, the needles Vare merely subjected to tension. Thus, the needles may be connected to eyed healds which in turn are connected to tension springs, the springs vextending in the one shedding movement of the needles and contracting to return the needles'.

The banks of needles are preferably arranged outside the Warp circle for accessibility. For eX- ample, the banks may be arranged one above another immediately outside the warp circle, leaving a gap between each into which the operating cam can penetrate, these cams being carried by supports arranged close to the outside of the banks. The cams are arranged on the supports at the different shedding points round the loom (there being as many of these points as there are shuttles) and operate on the needles of one or more banks in accordance with the pattern of fabric to be woven.

One form of apparatus according to the invention will now be described in greater detail with reference to the accompanying drawing,

Figure l of which illustrates in part cross-sectional elevati-on heald operating mechanism suitable for the weaving of 5-shaft satin with 150 warp threads per inch, incorporated in a loom of the type described in U. S. application S. No. 655,550 led 7th February, 1933. Y

Figure 2 is an enlarged section of part of the needle banks;

Figure 3 is a view of one of the needles;

Figures 4 and 5 are plan and elevation of a detail of Figure l; and

Figure 6 is a diagrammatic plan view of the Vshuttles of a Yl-shuttle loom of the type mentioned above, and also indicates the heald operating sequence, in accordance with the 5-shaft satin design shown in Fig. 7.

With referenceto Figure l a sheet of warp threads 8 proceeds downwardly in cylindrical form through a circular reed Il] past each shuttle II which forms the fabric I2 by laying weft in the shedded warps immediately above the spreading ring I3. Y

Above the level of the circular reed I0 and outside the cylinder of warps 3 a series of trick rings I4 is mounted on a number of pillars I5 arranged around the loom. The trick rings i4 are provided with radial, or substantially radial tricks or slots I 6 having a density (in this particular instance) of 30 to the inch, and arranged one above the other in a compact manner, as is apparent from the drawing. Needles I'I, consisting of thinY steel strips (Figure 3) are accommo'dated within the lengths of the tricks IG (Figures 1 and 2), their inner ends I8 reaching the inner edge of the trick rings I4 in the non-shedded position of the warps. Stops I9 are provided at about the mid-point of the length of the needles and abut against rings 2G on the under side of each ring I 4 which limit the inward movement of the needles. Y j

The inner ends I8 of the needles are enlarged to form eyes 2I to which are secured the healds proper 22. On the outer end of the needles II is a butt 23 for engagement by cams 24 (Figures 1, 3 and 4) formed on short segmental cam plates 25.

A pillar 2B lmounted just outside the outer edge of the trick rings I4 is arranged opposite the forward edge of each shuttle I I and carries supporting means for at least one of the short segmental cam plates 25 which extends radially inwards between the upper edge of the butt 23 on the outer end of the needles I'I and the lower face of the trick ring I4 immediately above. Each cam 24 comprises a curved strip secured to the under face of the cam plate 25 and projects downwardly between the two projections I9, 23 of the outer ends of the needles. The cam sweeps outwardly in a smooth curve to the extent of the heald lift required.

The lift of the cams may be such as to open the shed to the full width of a shuttle, or may be just suiiicient to commence a shed which is widened by the body of the shuttle on entering the shed. In the latter case, the heald eyes may be lengthened sufliciently to permit the threads to pass freely along them under the action of the shuttle as it widens the partly-formed shed. In either case the 5 length of each cam is such as to free the engaged needles as soon as the warp-shed formed thereby has reached the desired width.

The trick rings I4 moving round the loom at the same speed as the warps 8 and the cam plates 10 25 being held stationary, the projections I9, 23 of the needles I'I are engaged in turn by the cam 24 and so are drawn outwardly to the required amount, the outwardly drawn sheet being indicated at 9 in Fig. 1. As stated above the projec- 15 tions I9, 23 are released from engagement withY the cam 24 as the warp shed reaches the desired width, the shuttles II first holding the warps 8, 9 apart and then permitting them to move inwardly to the non-shedded or substantially vertical 20 position under the action of springs 26 connected to the inner ends 2I of thehealds, and by hooks 23 to a circular member 29 extending from a plate 3f) carried by the central shaft 3l of the loom and rotating at warp speed. 25

As is clear from Fig. l, 5 or even 8 banks of needles can be arranged in relatively little height, the needles I'I (and consequently the trick rings I4) being shallow and the cam plates 25 passing between the trick rings being very thin. 30 The trick rings provide for a support of the ne, closely-spaced needles I'I over their whole length, including the parts engaged by the cams 24, yet the radial distance occupied by the trick rings and the cam plates remains small. 35

For the weaving of 5-shaft satin, the warp threads are divided among 5 trick rin'gs I4 in the following mannerz Every fifth warp thread is threaded through the eye, or mail 32 Yof a heald 22 connected to 40;

one trick ring I4. Of the four remaining threads of each group of five, the fourth threads are threaded through the eyes 32 of the healds 22 of the next trick ring, and every second, fifth and third through the eyes of the heaids of the 45.A

At one shuttle the warp threads 9 retained by the 50iV needles IE5 of the lowermost trick ring are drawn outwardly, as shown in Figure 1, the threads connected to the needles of the remaining four banks keeping stationary; at the next shuttle ii after the return of the first thread under the 55i action of the corresponding spring 25 every fourth thread is drawn outwardly; on the next shuttle every second thread is drawn outwardly and Vso on, thus providing the shedding necessary for a 5-shaft satin. The order in which the banks 60 of needles are operated is indicated in Figure 6.

While eight trick rings are shown in Figure 1 it is to be understood that five only are in use in the production of a -shaft satin fabric. Thus with thirty tricks to the in-ch five trick rings accommodate needles per inch so that each warp thread is controlled by one needle. For more shafts a correspondingly greater number of trick rings is brought into use, and diiferent or more intricate designs may be obtained by 7-01 the use of more trick rings. Similarly, the number of tricks per inch may be varied by changing the trick rings for rings of finer or coarser pitch.

The trick rings are held in place one above the other by pins 33 (Figure 2) which project 75?? from the underside of each trick ring I4 and are engaged by extensions 34 of some of the trick walls immediately below. As many securing pins 53 as desired may be arranged at suitable intervals around the trick rings. The lowermost trick ring lll is provided with a depending lug 35 by which the ring is secured to a further ring 3S which in turn is secured to the supporting pillar I5 by a bolt 3l. The uppermost ring Ill has a plane upper surface merely serves to hold the needles l5 immediately beneath in place in their tricks ll.

The pillars I5 supporting the trick rings I4 are supported in turn on a ring 38 rotating at warp speed, while the pillars 25 carrying the cam plates 25 are mounted on a stationary ring 39 the function of which is described fully in U. S. application S. No. 655,560 filed 23rd May, 1933. Prefably means are employed to bring weaving to an end on breakage of warp or weft threads, as described, for example, in U. S. applications S. Nos. 655,560 and 672,379. In this way the shedding operation ceases and with the shuttles also rotating round the loom at warp speed as described in the above mentioned speciiications, the mechanism rotates idly until the whole loom is brought to a standstill for rectication of the defect. s

Where other regularly repeating patterns are required to be woven the number of shuttles employed must be divisible by the number of threads involved in each design; thus, for an -shaft satin the number of shuttles may conveniently be 16 or 24, which also enables the threads to be selected in several ways, including plain weaving.

It will be appreciated from the foregoing description that since at any particular shuttle the same set of warp threads is operated at each revolution of the loom, the number of warp threads must be divisible by five. The number of shedding points, and therefore the number of shuttles ymust also be divisible by five. Thus l shuttles may be employed round the loom periphery. With the arrangement described in U. S. application S. No. 683,620 led Aug. 18, 1933, a greater number of shuttles, such as 20 or more, may be used resulting in the loom being capable of a higher output.

It is to be understood that at any shuttle the needles ll of more than one trick I may be operated in accordance with the particular pattern to be effected. The pillars 26 are therefore arranged to carry more than one cam plate 25 at any one shuttle and at appropriate heights. Even if the needles'of one trick ring only are to be operated (as shown in Fig. l), it is arranged that each pillar 2li can support a cam plate at the height of any trick ring so that at any shuttle any particular set of` threads may be drawn outwardly. Spacing members lo maintain the cam plates 25 in correct relation, while packingrings di, of cam plate thickness, enable the members @t to be maintained in correctly spaced relation during the absence of a cam at any trick rlng.

What I claim and desire to secure by Letters Patent is:-

1. Shedding mechanism for a circular loom, comprising a plurality of banks of iine shedding needles adapted to control the warp threads, each bank having closely spaced slots adapted to permit sliding movement of the needles and to support the needles over a substantial portion of their length, and needle-engaging means between Which and said needles there is relative motion,

said needle-engaging means being disposed so as to engage the needles in a selected bank at a point along the supported length of the needles and to draw such needles under tension within the length of the needle slots, so as to effect a shedding movement of the warp threads controlled by said needles.

2. Shedding mechanism for a circular loom, comprising a plurality of banks of fine shedding needles adapted to control the warp threads, each bank having closely spaced slots adapted to; permit sliding movement of the needles and to support the needles over a substantial portion of their length, a butt 'formed on each needle at a point along the supported length thereof, and needleengaging means between which and said needles there is relative motion, said needle engaging means being disposed so as to engage the butts of the needles in a selected bank to draw such needles under tension within the length of the needle slots, so as to effect a shedding movement of the Warp threads controlled by said needles.

3. Shedding mechanism for a circular loom, comprising a plurality of circular banks of ne shedding needles adapted to control the Warp threads, each bank having closely spaced slots adapted to permit sliding movement of the needles and to support the needles over a substantial portion of their length, a butt formed on each needle at a point along the supported length thereof,

and cams, between which and said needles there is relative motion,` disposed round the banks, each cam being adapted to engage the butts of needles in a selected bank and thereupon to draw such needles under tension within the length of the needle slots so as to effect a shedding movement of the Warp threads controlled by said needles.

4. shedding mechanism for a circular loom, comprising a plurality of banks of fine shedding needles adapted to control the warp threads, each bank having closely spaced slots adapted to permit sliding movement of the needles and to suplport the needles over a substantial portion of their length, a butt formed on each needle at a point along the supported length thereof, and needleengaging means between which and the said needles there is relative motion, said needle-engaging means being disposed so as to engage the butts of the needles in a selected bank at intervals to draw such needles under tension within the length of the needle slots, so as to eli ect a shedding movement of the warp threads controlled by said needles.

5. shedding mechanism for a circular loom, comprising a plurality of trick-rings arranged in superposed relation and extending round the loom, a plurality of Warp-thread controlling needles slidably housed Within the tricks of said trickrings, a butt formed on eachneedle at apoint along the supported length thereof, and needle-engaging means between which and said needles there is relative motion, said needle-engaging means being disposed so as to engage the butts of the needles in a selected trick-ring to draw such needles under tension within the length of the tricks so as to separate the warp threads controlled by said needles from other warp threads to form a shed for entry of weft-inserting means.

6. Shedding mechanism for a circular loom, comprising a plurality of banks of fine shedding needles adapted to control the Warp threads, each bank having closely spaced slots adapted to permit sliding movement of the needles and to support the needles over a substantial portion of point along the supported length thereof, an eyed heald connected to each needle and adapted to accommodate at least one Warp thread, tension springs connected at one end to at least one heald and xed at the other end so as to maintain said heald under tension, and needle-engaging means between which and said needles there is relative motion, said needle-engaging means being disposed so as to engage the butts of the needles in a selected bank to draw such needles within the length of the needle slots against the tension in the tension springs and thereby to effect a shedding movement of ,the warp threads controlled by said needles.

7. Shedding mechanism for a circular loom,Y

comprising a plurality of Ybanks of ne shedding lneedles arranged outside the Warp circle and supported length thereof, andA needle-engaging means between which and said needles there is relative motion, said needle-engaging means being disposed so as to engage the butts of the needles in a selected bank to draw such needles under tension Within the length Vof the needle slots, and thereby to effect a shedding movement of the warp threads controlled by said needles.

8. Shedding mechanism for a circular loom,

comprising a plurality of trick-rings extendingY round the 100ml in superposed relation, adjacent rings being spaced apart, a plurality of Warpthread controlling needles slidably housed Within Ythe tricks of said trick-rings, a butt on each needle,

and at least one cam between which and the trickrings there is relative motion, said cam being.

in order to separate the Warp threads controlled 20 by said needles from other warp threads to form a shed for entry of weft-inserting means.

WILLIAM HOWARTH 

